A synthetic sequence for introduction of position-emitting 18F into the carbon-nitrogen sekeleton of 17-methyl or 17-cyclopropylmethyl-3,14,-dihydroxy-4,5-epoxymorphinan was developed. The potent opiate agonist oxymorphone and antagonist naltrexone respectively, were the prototypes for N-methyl and N-cycloprophylmethyl fluoro derivatives. The agonist was tritiated to high specific activity and preliminary experiments indicate successful synthesis of the 18F labeled morphinans.